Gel properties of hyaluronic acid dermal fillers

Dermatol Surg. 2012 Jul;38(7 Pt 2):1170-9. doi: 10.1111/j.1524-4725.2012.02472.x.

Abstract

Background: Most of the hyaluronic acid (HA)-based dermal fillers currently on the market are chemically modified with cross-linkers to improve the mechanical properties and duration in vivo.

Objective: To investigate differences in the properties of dermal fillers that can be related to the respective cross-linking and manufacturing methods used.

Methods and materials: Thirteen commercially available HA fillers were analyzed. Two different measures of gel strength were used: the elastic modulus (G') determined by rheology and a measure of the swelling capacity of the gel (c(min)). The degree of modification was determined using nuclear magnetic resonance spectroscopy, and the cross-linking ratio was determined using size exclusion chromatography coupled with mass spectrometry.

Results: There was a wide variation in gel strength, and the degree of modification varied between 1% and 8% for the HA fillers investigated.

Conclusions: Both measures of gel strength, G* and c(min), can be used because the results from the two methods are well correlated. No differentiation in filler properties could be seen as a result of manufacturing process used, except that the nonanimal stabilized HA stabilization process resulted in products with high gel strength and a low degree of modification.

MeSH terms

  • Chromatography
  • Cosmetic Techniques
  • Gels
  • Humans
  • Hyaluronic Acid / administration & dosage*
  • Hyaluronic Acid / chemistry
  • Magnetic Resonance Spectroscopy
  • Materials Testing
  • Rheology
  • Viscoelastic Substances

Substances

  • Gels
  • Viscoelastic Substances
  • Hyaluronic Acid